Imatinib mesylate (IMA) belonging to the selective tyrosine kinase inhibitor family has been proven to induce cardiotoxic effects along with therapeutic strategies. Nrf2-dependent ferroptosis has been implicated in the cardiotoxicity induced by IMA. The present study was designed to investigate the protective effects of berberine hydrochloride (Ber) on cardiac injuries induced by IMA and to explore its potential mechanisms. In H9c2 cells, cell viability, the generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and labile iron pool (LIP) levels were measured. In a mouse model of IMA-induced cardiomyopathy, serum biomarkers and cardiac tissues were examined. A western blot assay was performed to evaluate the expression of ferroptosis-related proteins in vitro and in vivo. Our results indicated that Ber increased cell viability and MMP and decreased cellular ROS and iron levels in comparison to the IMA group of H9c2 cells. In mice, Ber significantly improved cardiac status and attenuated the level of ferroptosis biomarkers including malonaldehyde (MDA) and iron content. Additionally, Ber downregulated the expression of transferrin receptor (TfR) and P53 and upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase-1 (NQO1), ferritin heavy chain-1 (FTH1), and glutathione peroxidase 4 (GPX4) in H9c2 cells and mice. The present data indicated that Ber has the potential to protect against IMA-induced cardiotoxicity, partly via inhibiting Nrf2-dependent ferroptosis.
SUN , a multi-targeted tyrosine kinase inhibitor , exerts cardiotoxicity which hinders its clinical use. It is necessary to elucidate molecular mechanism of SUN-induced cardiotoxicity. To elucidate molecular mechanism of SUN-induced cardiotoxicity and whether it is related to Nrf2-dependent ferroptosis , in vitro model with H9c2 cells derived from rat heart tissue and in vivo model (C57BL/6J male mouse) were used in the present study. In vivo model was established by oral treatment of SUN at dose of 10, 20, 40 mg/kg for 14 days. Body weight, ECG , plasma enzyme activities , histology staining were performed to evaluate heart function. Western-blot was performed to analyze the level of ferroptosis-related proteins. In vitro results indicated that SUN markedly induced ferroptosis embodied as collapsed MMP, accumulated iron and elevated ROS . In vivo results showed that SUN significantly impaired cardiac function. Abnormal electrocardiogram, increased serum CK and lactate LDH levels were significantly observed in SUN groups. Histology staining showed that SUN caused structural injuries and fibrosis deposition. Moreover, SUN increased the level of MDA and Fe 2+ content, decreased the level of GSH. Both in vitro and in vivo experiments indicated that SUN reduced the expression of Nrf2, HO-1, NQO1, GPX4 and FTH1, enhanced the TfR expression. This study suggested that oxidative stress and Nrf2-dependent ferroptosis played a vital role in SUN-induced cardiotoxicity.